The author of an earlier version of this page wisely noted: History “affects the records – what was recorded, who recorded it, who was recorded, what survives, and where it can be found.”
When we describe ourselves as being of Irish decent, we often unintentionally gloss over certain aspects of Ireland’s complex history. Ireland is a nation whose population (DNA) base has changed dramatically over the centuries. The Irish are descendants of the following major people groups:
A. The Gaelic Irish, who arrived 500-600 BCE (“Before the Christian or Common Era” - incorporating the “pre-Irish,” of whom little is known, who arrived before that – these original immigrants were religiously “pagans,” then Catholics);
B. The Vikings, a numerically small but very influential group who arrived ca. 800-1000 CE (“Common or Christian Era”) – “pagans,” then Catholics;
C. The “Old English,” including the Normans – Catholic colonists, who arrived ca. 1167-1558;
E. The Ulster Scots (Scots-Irish, mostly Protestants, most arrived after 1606 – there were and are, however, some Catholic Ulster Scots, e.g. branches of the Kennedys, MacDonalds, MacDonnells, Murrays, Napiers, etc. The Ulster Scots consist both of Scottish families who have “always” lived both in Scotland and on the NE Irish coast and more recent colonists.
As genetically-mixed-up Irish-Americans, we’re probably related, in some way, to ALL or most of these people groups.Britain and Ireland
It is important to emphasize that Britain’s and Ireland’s histories are, and always have been intertwined, for better or worse.
Ireland remained largely independent of England until the Reformation era, when King Henry VIII (1491-1547, King of England, 1509-1547) assumed the title of King of Ireland in 1541, with the backing of English and Irish Parliaments (the Irish Parliament consisted mostly of “Old English” aristocrats and really represented only a portion of the island). Henry’s daughter, Queen Elizabeth I (1533-1603, Queen of England, 1558-1603), was the first English monarch to exercise practical sovereignty over Ireland, a process that her successors perfected. After the Reformation, wars of religion, like the Wars of the Three Kingdoms (1639-1651) and the War of the Two Kings (fought mostly in Ireland, 1688-1691), eventually left the Catholic majority in Ireland in powerless subjugation, a condition they endured until “Catholic Emancipation” became a reality in the United Kingdom in 1829.
The 19th Century saw political campaigns, based among Irish Catholics and certain “Protestant Patriots,” to achieve: (1) renewed Home Rule for Ireland (the Irish Parliament had been merged with the British Parliament in 1800), and (2) land reform, to secure the status of tenants on their rented lands, or return landlord-owned properties to the Irish peasantry.
The Home Rule campaign was shepherded by Isaac Butt (1813-1879), Charles Stewart Parnell (1846-1891), and John Redmond (1856-1918), the three most prominent leaders of the Irish Nationalist (or Parliamentary) Party in the British House of Commons. When Home Rule within the United Kingdom was not achieved by the Nationalists, the Sinn Fein Revolt (1916-1921) eventually led to Home Rule of a different sort, with separate Parliaments both for the independent Irish Free State (later Republic) and the six predominantly Protestant counties of the Northeast, known thereafter collectively as Northern Ireland, an area which remains a part of the United Kingdom (both of these new political entities were established in 1921).
Land Reform was achieved incrementally through various acts of the British Parliament, 1870-1909, which often resulted from pressure asserted by Irish tenant-farmers through organizations like the Michael Davitt’s Irish National Land League and its successor the Irish National League (together active 1879-1898). Wyndham’s Land Purchase Act of 1903 was the most wide-ranging of these land laws, which essentially provided funds for government purchase of properties from landlords at suitable prices and provided grants and loans that allowed tenants to purchase these freed-up lands at reasonable rates.Migration from Ireland to America – 17th and 18th Centuries
It is difficult to estimate how many 17th-century migrants from Britain and Ireland were of Irish descent, although there was a noticeable Irish Catholic minority in the small population (25,000 in 1700) of early colonial Maryland, which initially had been founded as a refuge for British and Irish Catholics. Probably 90% of the Irish immigrants to American in the 18th century were Protestants, mostly Presbyterians from Ulster, who came because of changing agricultural practices (e.g. deforestation and a declining timber industry, a switch in land use to grazing from farming, a declining need for flax and the eventual collapse of the linen trade, occasional localized potato crop failures, decline in the tenuous practice of “Ulster Custom,” etc.) and rural violence (clashes between Protestant and Catholic tenants and laborers; conflicts with landlords).Migration from Ireland to America – the 19th Century
Irish immigration to America declined during the period of the American and French Revolutions and the Napoleonic Wars (1775-1815). This resulted mainly from the difficulty of sea travel during the many wars of the period and the significant participation of Irish males in the British army and navy.
Once peace returned to Europe, Irish immigration to America increased substantially, becoming extremely heavy during the period of the Great Famine, 1845-1852. Census records show that 262,000 Irish immigrants arrived 1820-1840, 1,695,000 arriving 1841-1860 (the “Famine Decades”), with a total 19th-Century migration (1820-1910) of 4,787,000. Roughly 477,000 Irish immigrants arrived in the 20th Century (1911-2010).Select Bibliography on Irish History 
2 From the severe on-again off-again Famine of 1845-1852, until the period of rapid decline in religious belief over the past several decades, the Irish population typically has identified as about 77% Catholic and 23% Protestant. Return
4 The Norman Empire at this time included England, Wales, much of lowland Scotland, and much of Western France. For several hundred yers hereafter, Irish cities often were bilingual, with in habitants speaking both Norman French and Irish. Return
5 Before 1541, the English King held the title of “Lord of Ireland,” from the Pope, who was persuaded by the Normans, shortly after Henry II’s invasion of Ireland, that while Ireland was potentially a separate, even independent, Kingdom it really was, for the present, a tribal wilderness that needed an outside governor. The Lordship made Ireland an (in essence) English “protectorate.” Since the Lord of Ireland was also the King of England, he was represented locally by a governor in Dublin, variously known as justiciar, lieutenant, or Lord Deputy, who presided over an Irish Parliament. Return